Ideas for raising the rear shocks on my '81 CB750

Been tearing into Rhonda, stripping her down slowly and getting to the point where I want to mock up the rear end and decide on what length suspension to fit in. Here's how she looks now -



A previous owner chucked some 11¾" shocks on the back which is all fine and dandy but they ain't gonna cut it for the build I have in mind. I want to raise the rear to give the bike a straighter look, thinking 14" - 15", but trying to figure out which size to order.

Is there a trick to playing around with the rear end to mock up how it'll look with different length shocks? 2x4's between the tire and frame? Just want to play around with height adjustments before I order the suspension.

Thanks as always,

-J

Go for stock length plus around 10 or 15 percent. When you get up to around 20% or more you have drastically altered the bikes geometry and if you aren't experienced in these adjustments you can find yourself in trouble handling wise.